Determination of Nucleotides and Nucleosides in Cereal Leaves by High Performance Liquid Chromatography

Sawert, Axel; Backer, A.I.; Plank-Schumacher, Karin-Heide; Wagner, Karl

doi:10.1016/s0176-1617(87)80054-8

Cited by 21 publications

(1 citation statement)

References 6 publications

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“…High nucleotide requirement theoretically includes plant developmental processes like germination, Xowering, pollen tube growth, and seed set (Kafer et al 2004). Unlike in bacteria and animal cells, considerable amounts of free bases and nucleosides seem to be present in plant tissues (Sawert et al 1987(Sawert et al , 1988Wagner and Backer 1992). Degradation of nucleotides, mainly from RNA breakdown in the vacuole, leads to the liberation of high concentrations of nucleobases and nucleosides during senescent stages, which can be recycled by adjacent tissues (Ashihara 1981;Wagner and Backer 1992).…”

Section: Introductionmentioning

confidence: 99%

Comparative studies on Ureide Permeases in Arabidopsis thaliana and analysis of two alternative splice variants of AtUPS5

Schmidt

Baumann

Schwarzkopf

et al. 2006

Planta

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The recovery of free purine and pyrimidine bases and their degradation products represent alternative pathways in plant cells either to synthesize nucleotides (salvage pathways) by low energy consumption or to reuse organic nitrogen. Such recycling of metabolites often requires their uptake into the cell by specialized transport systems residing in the plasma membrane. In plants, it has been suggested that several protein families are involved in this process, but only a few transporters have so far been characterized. In this work, gene expression, substrate specificities, and transport mechanisms of members of the Ureide Permease family in Arabidopsis (AtUPS) were analyzed and compared. Promoter-GUS studies indicated that the members of the family have distinct and partially overlapping expression patterns with regard to developmental stages or tissue specific localization. In addition, two alternative splice variants of AtUPS5, a novel member of the transporter family, were identified and investigated. The abundance of both alternative mRNAs varied in different organs, while the relative amounts were comparable. AtUPS5l (longer isoform) shares similar structural prediction with AtUPS1 and AtUPS2. In contrast, AtUPS5s (shorter isoform) lacks two transmembrane domains as structural consequence of the additional splice event. When expressed in yeast, AtUPS5l mediates cellular import of cyclic purine degradation products and pyrimidines similarly to AtUPS1 and AtUPS2, but differences in transport efficiencies were observed. AtUPS5s, however, could not be shown to mediate uptake of these compounds into yeast cells and might therefore be defective or have a different function.

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Section: Introductionmentioning

confidence: 99%

Comparative studies on Ureide Permeases in Arabidopsis thaliana and analysis of two alternative splice variants of AtUPS5

Schmidt

Baumann

Schwarzkopf

et al. 2006

Planta

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Influence of NO3 - and NH4 + nutrition on fermentation, nitrate reductase activity and adenylate energy charge of roots of Carex pseudocyperus L. and Carex sylvatica Huds. exposed to anaerobic nutrient solutions

Müller

Albers²,

Janiesch

1994

Plant Soil

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The adenylate energy charge, production of ethanol and lactate, and nitrate reductase activity were determined in order to study the influence of different nitrogen sources on the metabolic responses of roots of Carexpseudocyperus L. and Carex sylvatica HUDS. exposed to anaerobic nutrient solutions. Determination ofadenylates was carried out by means of a modified HPLC technique. Total quantity of adenylates was higher in Carex pseudocyperus than in Carex sylvatica under all conditions. In contrast, the adenylate energy charge was only slightly different between the species and decreased more or less in relation to the applied nitrogen source under oxygen deficiency. The adenylate energy charge in roots of plants under nitrate nutrition showed a smaller decrease under anaerobic environmental conditions than plants grown with ammonium or nitrate/ammonium. Roots of nitrate-fed plants showed a lower ethanol and lactate production than ammonium/nitrate-and ammonium-fed plants. Ethanol production was higher in C. pseudocyperus, formation of lactate was lower compared to that in Carex sylvatica. The activity of enzymes involved in fermentation processes (ADH, LDH and PDC) was enhanced significantly after 24 hours of exposure to anaerobic nutrient solutions in roots of both species. The induction of these enzymes was only slightly influenced by different nitrogen supply. In vivo nitrate reductase activity increased almost 3-fold compared to the aerobic treatment in both species and overcompensated loss of NADH reoxidation capacity caused by decrease of ethanol and lactate development. Induction of in vitro nitrate reductase activity was enhanced 313% in C. pseudocyperus and 349% in C. sylvatica under anaerobic environmental conditions and nitrate supply. These results indicate that nitrate may serve as an alternative electron acceptor in anaerobic plant root metabolism and that the nitrate-supported energy charge may be due to an accelerated glycolytic flux resulting from a more effective NADH reoxidation capacity by nitrate reduction plus fermentation than by fermentation alone.Abbreviations: ADH-alcohol dehydrogenase, AEC-adenylate energy charge, DMSO-dimethyl sulfoxide, EDTAethylen diamine tetraacetic acid, HPLC-high performance liquid chromatography, LDH-lactate dehydrogenase, NRA-nitrate reductase activity, PCA-perchloric acid, PDC-pyruvate decarboxylase, PVP-polyvinylpyrrolidone, PVPP-polyvinylpolypyrrolidone, TCA-trichloroacetic acid, Tris-tris(hydroxymethyl)aminomethane.

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The nucleoside and nucleotide contents of uredospores fromPuccinia graminis andPuccinia striiformis and of conidia fromErysiphe graminis, Erysiphe pisi, andTrichoderma harzianum

Pils¹,

Backer²,

Guduthur³

et al. 1991

Experimental Mycology

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Determination of Nucleotides and Nucleosides in Cereal Leaves by High Performance Liquid Chromatography

Cited by 21 publications

References 6 publications

Comparative studies on Ureide Permeases in Arabidopsis thaliana and analysis of two alternative splice variants of AtUPS5

Comparative studies on Ureide Permeases in Arabidopsis thaliana and analysis of two alternative splice variants of AtUPS5

Influence of NO3 - and NH4 + nutrition on fermentation, nitrate reductase activity and adenylate energy charge of roots of Carex pseudocyperus L. and Carex sylvatica Huds. exposed to anaerobic nutrient solutions

The nucleoside and nucleotide contents of uredospores fromPuccinia graminis andPuccinia striiformis and of conidia fromErysiphe graminis, Erysiphe pisi, andTrichoderma harzianum

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